HC-12 error correction

[iw2fvo]

Hi to all in this forum,
I am using the HC-12 serial on 433 mhz . Port rate is 9600 8 n 1 and the HC-12 is set as per default.
The rig works but at distance of about 50 meters i do have errors.
How could I correct these errors ?
Any configuration suggestion ?
Thanks
Ambro

[Scampy]

I'm assuming it needs an antenna to get the quoted 1000m range these things claim to have... Otherwise I'm guessing that it's simply weak signals at a 50m range that's causing the rig to stop working after 50m

[iw2fvo]

Both HC_12's have their own antenna.
Data are received but some errors are present.
Thanks

[Scampy]

Are you saying that up to around 50m data is sent and received OK and then above 50m data is being lost or corrupted.. if so it could be 101 things such as a range issue with the modules (ie they are designed to only work up to 50m), interferance, or the modules are faulty.

[iw2fvo]

Thanks,
the modules are brand new and they have a standard 433 MHz rubber/ plastic antenna.
They are sold for about 1000 meters: I just need about 100 meters...
Is there any program that could recover the comm errors ?
Thanks

[gadelhas]

Hi;

I use those modules a lot.
The 1000m are of course in best of the best conditions, but 50m are very bad.

Look at the datasheet, to increse the range you need to decrease the baud rate, increase the transmitting power, changing the FU mode, even changing the frequencie can help!
( Datsheet - http://www.seeedstudio.com/wiki/imag...ser_Manual.pdf )

[iw2fvo]

Thanks Gadelhas,
What port rate are you using ? I am using 9600 8 n 1.
I also use the default setting for the hc-12 : max power and FU_3 @ 4.2 vdc.
Do you use any correction algorithm ? LOOP_back or similar ?
I just dend data over the UART ..
Thanks a lot
Ambro

[gadelhas]

Thanks Gadelhas,
What port rate are you using ? I am using 9600 8 n 1.
I also use the default setting for the hc-12 : max power and FU_3 @ 4.2 vdc.
Do you use any correction algorithm ? LOOP_back or similar ?
I just dend data over the UART ..
Thanks a lot
Ambro

Hi;

In this moment i'm using 4800,8,n,1, max tx power.
No, i'm not using any correction, and i'm tx/rx about 83 bytes for message 1 time for second. ( NMEA RMC Message ). The distance is about 80m (+- 2m ) with 3 walls in the middle!

[iw2fvo]

yours are good result.
I will try @ 4800 8 n 1 .
Thanks
Ambrogio

[gadelhas]

yours are good result.
I will try @ 4800 8 n 1 .
Thanks
Ambrogio

Ok, than post your test result here. I'm curious. Can you also send me where you bought you rmodules?
I bought mine in Banggood!

[iw2fvo]

I bought two modules here:
http://www.ebay.com/itm/1Pcs-433Mhz-...-/171907297975.
Yesterday, because of my fault in power supply connection, one module crashed . I ordered one more this morning.
I am waiting to receive it ... but it will need some time .
Regards,
Ambrogio

[iw2fvo]

Good day,
I received the module this morning.
I wrote a simple program just to test the operative range of those modules.
I checked one way transmission only : tx is located in my home basement and the receiver is outside near the entrance gate.
The distance is few meter less than 50 with this set_up.
I used the default setting: 9600 8 n 1 and FU_3 mode. Power supply for the tx is around 3v3 and 4v0 for the receiver.
Two " rubber" antennas is used.
Sine I would like to test the Max communication range, I am asking if is there avaialable a " dedicated " tx pattern of data or text to be used for .
The gap or the repetion rate is interesting too.
The output from my set_up is attached here togethre with the relevant picbasic program used.
Thanks
Ambro

[gadelhas]

Good day,
I received the module this morning.
I wrote a simple program just to test the operative range of those modules.
I checked one way transmission only : tx is located in my home basement and the receiver is outside near the entrance gate.
The distance is few meter less than 50 with this set_up.
I used the default setting: 9600 8 n 1 and FU_3 mode. Power supply for the tx is around 3v3 and 4v0 for the receiver.
Two " rubber" antennas is used.
Sine I would like to test the Max communication range, I am asking if is there avaialable a " dedicated " tx pattern of data or text to be used for .
The gap or the repetion rate is interesting too.
The output from my set_up is attached here togethre with the relevant picbasic program used.
Thanks
Ambro

From my point of view is working fine.
You can try out my configs above. Also increasing the VCC of the TX to something like 4,5V will improve the transmission.

[iw2fvo]

I configured the module to operate at 4800 baud.
The max range is now 150 meters with very few errors.
It is OK for my application now.
Thanks
Ambrogio

[gadelhas]

I configured the module to operate at 4800 baud.
The max range is now 150 meters with very few errors.
It is OK for my application now.
Thanks
Ambrogio

Great!